Lets just start this review by saying that i am well travelled and have exceptionally high standards. I have stayed at top hotels around the world, both in developed and emerging markets and would consider myself to be discriminating.
The St. Regis is by far one of the best hotels where i have stayed. if you are not familiar with Bombay/Mumbai, the location is one of the best places where you can stay. Lower Parel is a high end area and the St. Regis is attached to one of the best shopping malls in Mumbai. That matters because you can simply exit the hotel and enter the mall and have access to a high end grocery store (because you have to pick up some mangoes there and some dried chili peppers that will knock your socks off), restaurants, and shopping if you are into that kind of thing.
The hotel well appointed with a good gym, nice restaurants (the highlight being Sahib Room, which is the best north Indian in the area), and decent bar options. Some people like the rooftop bar, but I found it to be just ok.
However the highlight, BY FAR, is the service. Upon entering the hotel, you are greeted by several smiling staff, who are well dressed, greet you warmly and direct you to the elevators which take you upstairs to the check in. We received Butler service who showed us the room and were literally at our beck and call for all matters of service. My butler was named Alyshia and i was warmly greeted by her every morning. She remembered my name, asked me how things were and seemed genuinely concerned by my well being. On my first night there were some noises that I heard in the other room (strangely thin walls, one of my few complaints) due to it being wedding season and a group being relatively loud. I explained to them that I had problems sleeping as a result and she was very dismayed, communicated this to the entire "team" of butlers who separately approached me, apologized and had researched the matter and learned that the offending party would be leaving the hotel that day. The following morning, they inquired as to whether i had slept better and if there were further noises.
3 months later I came to Mumbai and had dinner at Sahib room, but unfortunately had to stay in a different part of Mumbai to the monsoon rains making travel complex (stayed at the Grand Hyatt, which was fine, but not nearly as memorable). However I ran into Alyshia, and told her what a wonderful stay that I had. She remembered my name! She also chastened me for not writing a review on my experience, so here it is!
I will be staying at the St Regis the next time I come to Mumbai for SURE!